Are the Helicopters About to Take Off?

St. Louis Fed president calls for "quantitative easing" to prevent Japan-like deflation. Why the flip-flop?

IN WHAT MAY BE PREPARATORY STEP for a major shift in the U.S. monetary policy, St. Louis Federal Reserve Bank President James Bullard warned the U.S. is closer to succumbing to a Japanese-style deflation than any recent time, which he urged be countered with "quantitative easing."

Quantitative easing, or QE, is economists' jargon to describe the Fed's massive purchases of $1.7 trillion in Treasury, agency and mortgage-backed securities, a program that started in March 2009 and ended a year later. The purchases...